The present invention relates to a seat belt device for a vehicle.
There are vehicles including a rear row seat which is disposed behind a front row seat (a driver's seat and a passenger seat) and available for plural passengers sitting thereon in a vehicle width direction. Further, a three-passenger-sitting seat is known as such rear row seat, which includes a central seat portion for a passenger sitting at a central position thereof and side seat portions located at both sides of the central seat portion for two side-sitting passengers.
Meanwhile, seat belt devices are provided respectively for passengers sitting on the seat. In the above-described three-passenger-sitting seat, a seat belt device is also provided for a central passenger sitting on the central seat position of the rear row seat. Herein, the seat belt device for the central passenger is needed to be configured of a three-point type of seat belt recently.
Generally, the three-point type of seat belt has the following structure. Namely, a seat belt withdrawn from a seat belt retractor extends via a seat belt anchor disposed at a high position of a vehicle body, and a tip of the seat belt is normally connected with a first attaching portion as a fixing point to the vehicle body which is disposed at either one side of the above-described central seat portion. Meanwhile, there is provided a coupling member which is guided through the seat belt and capable of moving between the seat belt anchor and the first attaching portion, and the coupling member is coupled detachably to a second attaching portion as another fixing point to the vehicle body which is disposed at the other side of the above-described central seat portion. The seat belt anchor is disposed behind the passenger to be retrained and offset from the passenger in the vehicle width direction (normally, it is attached at a side wall member of vehicle body, such as a center pillar or a rear pillar, which is located at a side end portion of the vehicle). Further, the seat belt retractor is usually attached at the side end portion of the vehicle (side wall member of vehicle body), corresponding to a position of the seat belt anchor. Also, generally the above-described first attaching portion which the tip of the seat belt is normally connected with is located at a side of the side wall member of vehicle body, while the above-described second attaching portion is located at an inside of the vehicle body.
Herein, when the three-point type of seat belt device is applied to a passenger sitting on the central portion of the rear row seat, there may be a problem with the position of the seat belt retractor. This is because there exists no normal side wall member of vehicle body for attaching the retractor beside the passenger sitting on the central seat portion due to existence of the left and right seat portions. A structure in which a seat belt retractor for the central passenger on a rearmost seat is disposed in a corner portion (a space in a vehicle compartment) near an upper portion of a rear pillar is disclosed in Japanese Laid-Open Patent Publication No. 2000-1156. Namely, the patent publication discloses that there is provided a bracket which connects a rear end portion of a roof rail constituting a side edge portion of the roof with a side end portion of a rear header constituting a rear edge portion of the roof, and the retractor is attached at this bracket.
The structure disclosed in the above-described patent publication may be preferable in utilizing a dead space of a vehicle having an enough space in the corner portion near the upper end of the pillar in the vehicle compartment. However, it may be difficult from a design stand point to locate the retractor in this position for a vehicle which does not have enough space in the corner portion. Particularly, since the seat belt withdrawn from the retractor needs to extend toward the seat belt anchor disposed in a proper position for the central passenger on the rear row seat, spaces for locating not only the retractor but also the seat belt which is withdrawn from the retractor and extends toward the seat belt anchor should be considered. Accordingly, it may be actually impossible from a head-clearance-acquirement stand point as well to locate the retractor in this position for the vehicle not having enough space at this corner portion. In other words, it may be difficult that the technology disclosed in the patent publication can satisfy both proper vehicle design, particularly a rear part design of the vehicle behind the rear row seat, and acquirement of such enough head clearance.